The biggest turnout in Polish parliamentary elections since the end of communism in 1989 has produced a sweeping victory for the liberal Civic Platform party.

The scale of the victory surprised many analysts who had expected a much closer race.

But it appears the outgoing 58-year-old prime minister, Jaroslaw Kaczynski, who called the elections two years early hoping his support base would increase, underestimated how much he had divided Polish society in the past two years.

Many Poles believe Mr Kaczynski, and his twin brother Lech, who will remain the country's president until 2010, focused too much on worrying about the pernicious influence of former communists on society and picking unnecessary arguments with Germany over World War II.

They were also concerned that his Law and Justice party were accused of using the state apparatus to spy on his political opponents.

The leading daily Gazeta Wyborcza summed up the mood of the anti-Kaczynski supporters.

"Poles rejected Law and Justice's populism, insinuations, fear and its pitting one social group against another. They rejected the policy of conspiracy theories, false pride, truly nationalist megalomania, arrogance and anti-German phobias," the paper's deputy editor-in-chief Jaroslaw Kurski wrote in a front page editorial.

Hopes for fresh start

Radoslaw Sikorski served as Mr Kaczynski's defence minister but he resigned after a clash with the twins and ran as an MP for Civic Platform.

Poles voted in droves - and swung away from rural conservatism

"I think the young urban population and the emigres opted for a pro-European, more open and a more optimistic kind of Poland. It was both a pro-Civic Platform vote and also a punishment for mistakes that were clearly made," Mr Sikorski told me.

Civic Platform is expected to form a coalition government with the small Peasants' Party in the coming weeks.

Civic Platform's 50-year-old leader Donald Tusk has promised Poles a calmer, inclusive style of government under which all Poles can prosper.

During campaigning he repeatedly said Poles should expect an "economic miracle". He said the country could take advantage of its skilled labour force and EU funds to replicate the success stories of countries like Ireland.

"This result means that Poland's politics will look very different. This will be a forward-looking, modernising government trying to heal the wounds of the last two years, during which the Kaczynski brothers divided society," Pawel Swieboda, head of the think-tank DemosEuropa, told the BBC.

Mr Tusk has promised to speed up privatisation, lower taxes and cut out bureaucratic procedures from business to encourage investors.

US ties reviewed

There will also be changes of style in foreign policy. Poland will become a more co-operative and predictable partner in Europe but the United States will remain a key ally.

Law and Justice made great play of rooting out corruption

Washington may find the new government a more demanding partner.

Civic Platform has already signalled its intention to bring the 900 Polish troops serving in Iraq home next year. It might also take a tougher stance in negotiations to host a US missile defence base in Poland.

"Civic Platform will want to negotiate in a tougher fashion with the United States because it considers that our policy vis-a-vis Washington has been too soft at the edges," Mr Swieboda said.

Mr Kaczynski will remain a dominant figure in Polish political life and will lead the largest opposition party. Around five million Poles voted for his Law and Justice party, more than during its election victory two years ago.

One of the other main results of the election is the removal of the smaller, radical fringe parties from parliament. Until the summer the far-right League of Polish Families and the populist, rural-based Self Defence party were junior members of Mr Kaczynski's coalition government. The two parties failed to win enough votes to enter parliament.

"Jaroslaw Kaczynski's great merit, and this benefits everyone, will be the eventual destruction of the populist parties - the League of Polish Families and Self Defence," wrote columnist Piotr Zaremba in the Dziennik newspaper.